1. Field of the Invention
This invention relates to a novel phthalocyanine compound, a method for the production thereof, and uses found therefor. More particularly, it relates to a phthalocyanine compound which exhibits high transmittance, particularly to a visible light ray, enjoys a high efficiency in cutting the near infrared ray, excels in the ability to absorb the near infrared ray, manifests fine compatibility with resin, and excels in such special qualities as heat resistance, light resistance, and resistance to weather and a near infrared absorbable dye. This invention further relates to a method for producing the phthalocyanine compound with high efficiency at a high purity.
Further, this invention relates to a heat wave shielding material containing the phthalocyanine compound or the near infrared absorbable dye, i.e. one of the use inventions for the phthalocyanine compound or the near infrared absorbable dye mentioned above, and more particularly relates to such heat wave shielding materials as windows in buildings or vehicles, light windows, automobile garages, ceiling domes, horticultural hothouses, sunglasses, and goggles which possess opacity or transparency and serve the purpose of shielding heat wave.
Further, this invention relates to a plasma display grade filter formed by incorporating therein the phthalocyanine compound or the near infrared absorbable dye mentioned above, i.e. another of the use inventions for the phthalocyanine compound or the near infrared absorbable dye mentioned above, and more particularly relates to a plasma display grade filter which serves the purpose of cutting the near infrared ray (750 to 1,100 nm) emanating from a display and preventing the peripheral electronic devices from producing a malfunction. More particularly, this invention relates to a plasma display grade filter containing the phthalocyanine compound or near infrared absorbing dye mentioned above as a near infrared absorbent, exhibiting high transmittance to the visible ray and allowing a highly efficient cut of the near infrared ray.
The phthalocyanine compound or the near infrared absorbable dye of this invention manifests an excellent effect when it is used as a near infrared absorbent for the non-contact fixing toner as in the flash fixing or as a near infrared absorbent for the insulating heat accumulating fibers.
The phthalocyanine compound or the near infrared absorbable dye of this invention manifests an excellent effect when it is used as a near infrared absorbable dye or a near infrared sensitizer for writing or reading data in an optical recording medium operating with a semiconductor laser, a liquid crystal display device, or an optical character reader, as a photothermal converting agent in a thermosensitive transfer-thermosensitive perforated plate, a near infrared absorbable filter, an eye strain preventing agent, or a photoconductive material, and as an oncotherapy grade photosensitive dye acquiring highly satisfactory permeation through tissues and absorbing light in a long wavelength range, as a color braun tube grade selective absorbing filter, as a color toner, as an ink jet grade ink, as an indelible bar code ink, and as a near infrared absorbing ink.
2. Description of the Related Art
In recent years, heat wave shielding materials which are adapted to absorb near infrared ray have been encouraging introduction of varying uses and the desirability of developing such heat wave shielding materials with improved performance has been finding enthusiastic recognition. The following uses may be cited as typical examples.
Since such materials as methacrylic resin and polycarbonate resin possess outstanding transparency and weatherability, they have been heretofore found utility in the so-called glazing applications such as windows in buildings and vehicles, ceiling windows, doors, and ceiling domes. Since they also exhibit high transmittance to the heat wave in the sunlight, they are at a disadvantage in inducing a copious rise of internal temperature as when they are directly exposed to the sunlight. To overcome this defect, these materials are urged to be so adapted as to prevent their interior temperature from rising and, at the same time, permit fully satisfactory admission of the visible light.
At present, in the cultivation of plants, hothouses and PVC film houses are extensively utilized for the purpose of improving the harvests of crops in quality or changing the time of harvest. One of the tasks that are imposed thereon comprises preventing their interior temperature from rising particularly in the summer season. It is well known that the light in the near infrared region affects the control of the growth of plants. The addition of an absorbent for the light in the near infrared region is aimed at this control. For this reason, the desirability of developing a heat ray shielding film which manifests an expected effect without substantially impeding passage of the visible light which is indispensable to the growth of plants has been finding recognition.
At present, the near infrared is frequently utilized in starting or stopping such electrical products as magnetic tapes. Though the near infrared serving this purpose requires to be shielded from an external near infrared, the demand for utilizing this near infrared for such applications is persisting.
The infrared ray contained in the sunlight or the infrared ray contained in the ray of light radiated from the terminal display of a computer or emitted during the work of welding is harmful to the human eyes. Thus, the demand for sunglasses, ordinary spectacles, contact lenses, and goggles which are effective in shielding the heat ray for the purpose of protecting the human eyes is also persisting.
In the circumstances, therefore, several heat ray shielding materials have been proposed to date. The resins which are used in these heat ray shielding materials include such transparent materials as polycarbonate resin, acrylic resin, and vinyl chloride resin, which are properly selected to suit the purpose of application. As typical examples of the additive for shielding the heat ray, numerous dyes and dyes which are capable of absorbing light in the near infrared region have been known. The heat ray shielding materials using such dyes and dyes have been also proposed. They, however, are deficient in transparent because they invariably exhibit strong absorption in the visible region.
For the purpose of solving these problems, U.S. Pat. No. 4,296,214, for example, has proposed a method which comprises adding a dye exhibiting only small absorption in the visible region. This method, however, has the problem of inevitably requiring the dye to be added in a large amount enough to manifest the effect of shielding the heat ray because of the poor ability to absorb the near infrared ray and consequently inducing degradation of the transmittance to the visible ray and impairing the transparency.
JP-A-51-135,886, U.S. Pat. No. 4,763,966, U.S. Pat. No. 4,755,012, etc. have proposed methods which reside in adding a dye exhibiting absorption in the near infrared region. The dye, however, has the problem of finding only limited use because it is deficient in solubility, exhibiting inferior compatibility with resin, and allowing fully satisfactory uniformity.
For example, a composition incorporating an inorganic dye therein has proposed. Though this composition indeed manifests a satisfactory effect in shielding the heat ray, it fits only limited use because it is low passing ratio of the visible ray and leanes haze. Further, JP-A-01-161,036, JP-A-03-227,366, etc. have proposed methods which comprises incorporating such additives as tungsten hexachloride. Though these methods bring a fully satisfactory effect in shielding the heat ray, they are at a disadvantage in suffering from poor light stability and have the problem of imposing a limit on the field of utility because of the high price of additive to be used.
The idea of using an infrared absorbent which is formed of an organic dye has been conceived as disclosed in JP-B-43-25,335, for example. The heat ray shielding material using this infrared absorbent imparts the sensation of transparency and excels in workability. As stated in JP-B-43-25,335, however, organic infrared absorbents generally succumb to decomposition at a temperature exceeding 200.degree. C. and, therefore, suffer from such restrictions on handling as substantially finding only limited utility in the cast polymerization.
For the purpose of preventing such an infrared absorbent from the problem of heat resistance, the idea of manufacturing a laminate by a method which comprises forming a film of a composition resulting from adding an infrared absorbent of a low heat-resisting temperature to a transparent resin of a low forming temperature and thermally superposing the film on a transparent resin sheet of a high forming temperature has been conceived as disclosed in JP-A-03-161,644, for example. This method, however, has not constituted itself a substantial liberation of the infrared absorbent from the problem of heat resistance. Further, the film containing this infrared absorbent is fairly expensive because it by nature needs to be formed by cast polymerization.
Among the inventions perfected and proposed by the present inventors with a view to solving the problems mentioned above are counted the phthalocyanine compound-containing heat ray shielding materials which, as disclosed in U.S. Pat. No. 5,435,462, JP-A-06-25,548, and U.S. Pat. No. 5,359,056, excel in the ability to absorb near infrared ray, excel in the compatibility with resin, and exhibit highly satisfactory resistance to heat and light. The phthalocyanine compound-containing heat ray shielding materials mentioned above allow relatively satisfactory passage of the visible ray, exhibit an excellent effect in shielding the heat ray, and fit utility as resin plates, sheets, or films in such objects as windows in buildings and vehicles, ceiling windows, doors, automobile garages, ceiling domes, horticultural hothouses, sunglasses, and goggles which possess opacity or transparency and serve the purpose of shielding the heat ray. (The present inventors, as specifically described herein below, have pursued a deliberate study further on the inventions disclosed in U.S. Pat. No. 5,435,462, JP-A-06-25,548, and U.S. Pat. No. 5,359,056 to discover that among the compounds neither specifically cited in the specification nor demonstrated by means of a working example are included such phthalocyanine compounds as manifest the conspicuous effect of allowing excellent transmittance to the visible ray as compared with the effect disclosed in U.S. Pat. No. 5,435,462, JP-A-06-25,548, and U.S. Pat. No. 5,359,056. They have continued a diligent study further on the outcomes of the study to find that, even in the other technical field (application), the phthalocyanine compounds manifest the conspicuous effect of allowing exaltation of the transparency.)
In other technical field than those mentioned above, U.S. Pat. No. 5,516,899 discloses a phthalocyanine compound which has either of SR and NHR (R denoting such an organic group as substituted or unsubstituted alkyl group or aryl group) attached as a substituent respectively at 15 of the total of 16 positions of a phthalocyanine nucleus available for substitution. According to the specification, this compound is purportedly useful for the purpose of absorbing the electromagnetic wave emitted from a laser source and usable for the purpose of coating an optical data memory disk. This compound, like the compounds disclosed in U.S. Pat. No. 5,435,462, JP-A-06-25,548, and U.S. Pat. No. 5,359,056 mentioned above, does not deserve to be called satisfactory in terms of the transmittance to the visible ray.
Further, the prospect of the plasma display finding utility in large thin-wall television sets or as thin-wall displays has come to attract attention in recent years. The large thin-wall television sets and the thin-wall displays which actually use the plasma display have already making a market debut. The near infrared ray emanating from the plasma display, however, has been causing the problem of compelling such peripheral electronic devices as cordless phones and video decks using a near infrared remote control to produce an erroneous operation. While it has been known to manufacture a near infrared absorbing filter by the use of a near infrared absorbable dye, a typical measure for preventing the display from inducing the erroneous operation has not been fully developed. Barely, JP-A-09-230,134 has proposed a method for solving the problem in question by the use of a plasma display grade filter containing a metal complex compound. The metal complex compound, however, has the problem of inferior compatibility with resin because it possesses such low solubility that it will hardly melt in a given resin even after they are kneaded together at such a high temperature as 260.degree. C. or 280.degree. C. for a long time. It further does not manifest a fully satisfactory effect in absorbing the near infrared ray because the amount thereof to be added and the kind of resin to be mixed therewith have their own limits. While the desirability of developing a plasma display grade filter capable of manifesting a perfect effect in absorbing the near infrared ray has been finding recognition, no proposal has yet been advanced regarding a method for coping with the problem under discussion by the use of a plasma display grade filter containing such a phthalocyanine compound as effectively forms a near infrared absorbent.
This invention has been initiated in the light of the true state of the prior art in the various fields (applications) which allow utility of phthalocyanine compounds.
Specifically, this invention has been produced for the purpose of solving the technical problems to be encountered in the various fields (applications) which allow utility of phthalocyanine compounds. An object of this invention is to provide a phthalocyanine compound and a near infrared absorbable dye which exhibit particularly high transmittance to the visible ray, offer a highly efficient cut of the near infrared ray, excel in the ability to effect selective absorption in the near infrared region, excel in the compatibility with resin, and excel in the resistance to heat, light, and weather conditions.
A further object of this invention is to provide a phthalocyanine compound and a near infrared absorbable dye which are capable of controlling the absorption wavelength fitting the purpose of use in the near infrared region (an absorption wavelength region of 750 to 1,100 nm) and exhibiting excellent solubility in such solvents as, for example, hydrophilic solvents, alcoholic solvents, oleophilic solvents, ketones, and aromatic hydrocarbon solvents.
Another object of this invention is to provide a method for producing the phthalocyanine compound mentioned above with high efficiency at a high impurity.
Still another object of this invention is to provide an inexpensive heat ray shielding material which allows selective absorption of light in the near infrared region and performs an effective cut of the heat from the sunlight while keeping the transmittance in the visible region at a relatively high level. To be specific, this invention intends to provide a heat ray shielding material capable of manifesting an outstanding shielding effect by developing a transparent resin containing a novel phthalocyanine compound excelling in the ability to effect selective absorption of light in the near infrared region, excelling in the compatibility with resin, and offering excellent resistance to heat, light, and weather conditions.
Still another object of this invention is to provide a heat ray shielding material which is usable in a wide variety of applications by using invariably inexpensive organic materials for the components of a heat ray shielding material. It further resides in ensuring impartation to the phthalocyanine compound of excellent resistance to heat thereby allowing provision of a heat ray shielding material which can be manufactured from a standard thermoplastic resin by the use of such a method of molding of excellent productivity as the injection molding or the extrusion molding, for example.
Still another object of this invention is to provide a practical plasma display grade filter which allows an effective cut of light in the near infrared region, i.e. 750 to 1,100 nm, preferably 800 to 1,000 nm, liable to induce peripheral electronic devices to produce an erroneous operation due to the light escaping from the display and, at the same time, exhibits a high transmittance to the visible ray without sacrificing the clarity of display.